October is designated by the Catholic Church as the “Month of the Rosary” because in this month the Church celebrates the Marian advocation of “Our Lady of the Rosary” on Oct. 7th.

The feast of Our Lady of the Rosary, also celebrated as Our Lady of Victory or Victories, was established by Pope St. Pius V in 1571 to celebrate the miraculous victory of the Christian forces in the Battle of Lepanto on Oct. 7th of that year. Two years before establishing the feast, in 1569, Pope St. Pius V officially approved the rosary in its present form with the papal bull Consueverunt Romani Pontifices (“The Roman Pontiffs are accustomed,” the first words of the document). In a development from earlier methods of praying the rosary, the new version included the second half of the Hail Mary, as well as the “Glory Be” prayer at the end of each mystery.

In Consueverunt Romani Pontifices, St. Pius V established the two essential elements of the rosary: vocal prayer and mental prayer. The dedication of the month of October to the Holy Rosary became common in the Church thanks to Pope Leo XIII, an enthusiastic promoter of the rosary. In the span of only five years, Pope Leo wrote eleven encyclicals on the rosary.